[infra] Translate _sources.gypi files to _sources.gni files

runtime/lib/profiler_sources.gni

Index: runtime/lib/profiler_sources.gni
diff --git a/runtime/lib/profiler_sources.gypi b/runtime/lib/profiler_sources.gni
similarity index 65%
rename from runtime/lib/profiler_sources.gypi
rename to runtime/lib/profiler_sources.gni
index 9175427107a3e4c8ffcb9d65e9a7d2c5ebb33ba4..b27bc8838424a42afa95aa02c756d168a5e0a03b 100644
--- a/runtime/lib/profiler_sources.gypi
+++ b/runtime/lib/profiler_sources.gni
@@ -1,12 +1,6 @@
-# Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
+# Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 # Sources list to keep vm/BUILD.gn generate_core_libraries happy.
-
-{
-  'sources': [
-    'empty_source.dart'
-  ],
-}
-
+profiler_runtime_sources = [ "empty_source.dart" ]